National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Enantioselective synthesis. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

One-Step Synthesis of Ordered Two-Dimensional Assemblies of Silver Nanoparticles by the Spontaneous Reduction of Silver Ions by Pentadecylphenol Langmuir Monolayers

Abstract: The single-step synthesis of silver nanoparticles by the reduction of silver ions present in the subphase under alkaline conditions by 3-pentadecylphenol (3-PDP) Langmuir monolayer and their assembly into ordered two-dimensional structures is described. The reduction of the silver ions occurs by electron transfer from ionized phenol groups of 3-PDP, which then stabilize the particles against aggregation. Similar reduction of aqueous silver ions was carried out at the interface with toluene bearing 3-PDP and yielded monodisperse silver nanoparticles that may be separated as a dry powder and redispersed in a range of organic solvents. The mechanism of reduction of silver ions by 3-PDP under alkaline conditions was studied by UV−visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, transmission electron microscopy (TEM), and chemical analysis by X-ray photoelectron spectroscopy (XPS), and is discussed in detail.

Role of stem cell derived exosomes in tumor biology.

Abstract: Exosomes are nano-scale messengers loaded with bio-molecular cargo of RNA, DNA, and Proteins. As a master regulator of cellular signaling, stem cell (both normal, and cancer stem cells) secreted exosome orchestrate various autocrine and paracrine functions which alter tumor micro-environment, growth and progression. Exosomes secreted by one of the two important stem cell phenotypes in cancers a) Mesenchymal stem cells, and b) Cancer stem cells not only promote cancerous growth but also impart therapy resistance in cancer cells. In tumors, normal or mesenchymal stem cell (MSCs) derived exosomes (MSC-exo) modulate tumor hallmarks by delivering unique miRNA species to neighboring cells and help in tumor progression. Apart from regulating tumor cell fate, MSC-exo are also capable of inducing physiological processes, for example, angiogenesis, metastasis and so forth. Similarly, cancer stem cells (CSCs) derived exosomes (CSC-exo) contain stemness-specific proteins, self-renewal promoting regulatory miRNAs, and survival factors. CSC-exo specific cargo maintains tumor heterogeneity and alters tumor progression. In this review we critically discuss the importance of stem cell specific exosomes in tumor cell signaling pathways with their role in tumor biology.